1. Field of the Invention
The present invention relates to a measuring method and apparatus for measuring quasi-electrostatic field occurring from contact between tires of a running vehicle and the road surface and, in particular, to a measuring method and apparatus which can be preferably applied to estimating the state of the road surface or detecting the running state of the tires.
2. Description of the Related Art
There have been technologies proposed for detecting the acceleration of a tire as an indicator in identifying the state of the road surface as disclosed in the prior art document listed below (see Patent Document 1).